Selective load balance with cookie persistence

You can't, easily.

 

When the cookie persistence timer expires, the browser does not send the cookie, so the LTM makes a new load-balancing decision.

 

Without the cookie, the LTM does not have any record of the last load-balance decision made, so it cannot deliberately choose a different server.

 

You could write an irule that also records load-balancing decisions, and for every new load-balancing decision checks to see if the new decision is the same as the old one, and if not, then reselect. But this approach will take some significant memory in tmm as every client will need a record and the record could be required to remain for an arbitrary length of time - is this only for testing purposes or is this required in production?